The methods of the destruction of cellular tissues in situ has been used in the treatment of many diseases, or as an adjunct to surgical removal procedures. One method used requires heating the tissues, and causing them to shrink and tighten. It is often less traumatic than surgical procedures and may be the only alternative method, wherein other procedures are unsafe, complicate, or expensive. Ablative treatment devices have an advantage because of using a destructive energy that is rapidly dissipated and reduced to a non-destructive level by conduction and convection, to forces of circulating fluids and other natural processes.
Devices using microwave energy, radiofrequency energy, ultrasonic energy, cryogenic means, laser energy, and tissue destructive substances have been used to destroy malignant, benign, and other types of cells and tissues from a wide variety of anatomic sites and organs. Tissues treated include isolated carcinoma masses and, more specifically, organs such as the prostate, glandular and stromal nodules characteristic of benign prostate hyperplasia. These devices typically include a catheter or cannula which is used to carry a radiofrequency electrode or microwave energy antenna, through a duct, to the area of treatment, and applying energy diffusely through the duct wall into the surrounding tissues in the targeted directions.
Of particular interest to the present invention are ultrasonic energy therapeutic protocols, which have been proven to be highly effective. The traditional radiofrequency ablation provides therapeutic energy by heat conduction while the ultrasonic ablation can provide a deeper energy penetration. By heating the tissues, and causing them to shrink and tighten, the excess mass of tissue can be reduced to clear the air passageway. Ultrasonic energy, when coupled with a temperature control mechanism, can be supplied to the device-to-tissue contact site and deep into the tissue under precisely to obtain the desired tissue treatment. Ultrasonic energy is conveyed to the tissue by heat conduction and penetration.
To be more efficient in ultrasonic energy ablation, an ultrasonic transducer means with a vibration capability can be used to simultaneously deliver the massage therapy to the target tissues. The electric toothbrush with vibration has been disclosed in the following patents: Suyama in U.S. Pat. No. 4,944,296, Ng in U.S. Pat. No. 5,283,921, Hwang in U.S. Pat. No. 5,381,576, Okada in U.S. Pat. No. 5,421,726, Mei in U.S. Pat. No. 5,617,603, and Hahn in U.S. Pat. No. 5,651,157. All the above patents disclose the advantage of an electric toothbrush with vibration. However, they do not teach using an ablation means with vibration capability to treat the tissues for therapeutic purpose.
On the other hand, Imran in U.S. Pat. No. 5,281,218 entitled "Catheter having needle electrode for radiofrequency ablation" teaches a method using a needle electrode that is attached onto a catheter for radiofrequency ablation. Though a needle-like electrode is beneficial to ablate a tissues point, it is not disclosed that the particular needle electrode could possibly combine pressure therapy and ultrasonic energy for proper contact with the target tissues. The "pressure therapy" is defined in this invention as applying appropriate pressure onto the tissues by a medical device.
Edwards et al. in U.S. Pat. No. 5,456,662 entitled "Method for reducing snoring by RF ablation of the uvula" teaches a medical ablation method for reducing snoring wherein a flexible RF electrode wire is inserted into the uvula and RF energy is applied to the uvula tissues to cause internal lesions. Edwards et al. does not disclose a catheter to ablate tissues, having the capability for delivering ultrasonic energy and pressure therapy for deep tissue treatment.
Marcus et al. in U.S. Pat. No. 5,295,484 and Castellano et al. in U.S. Pat. No. 5,606,974 teach a catheter system having ultrasonic device for intracardiac ablation of arrhythmias. However, neither discloses a medical device having ultrasonic energy and pressure/vibrational therapy to treat the tissues effectively.
Therefore, there is a need for an improved medical device and methods using the ultrasonic energy to treat uvular, airway obstructions, polyps, or tumors, while applying pressure and/or vibrational massage therapy.